Insulated stone, wall structure using same and method of assembling a wall structure

ABSTRACT

The present invention discloses a manufactured stone comprising a body and an insulating core. The body has a base, an exterior portion and an interlocking mechanism. The exterior portion has an aesthetic face. The interlocking mechanism is adapted to interlock with another similar manufactured stone. The insulating core is at least partly imbedded in the body. The insulating core has a thickness sufficient to provide the body with an R-value of at least R8. The manufactured stone may also be made with a mid portion placed between the base and the exterior portion. The mid portion is recessed both from the base and the exterior portion. In that case, the R-value may be less than R8. The invention also discloses a wall structure comprising, from an interior to an exterior, a wall framing, a sheathing material and a plurality of manufactured stones. The wall framing is made of a plurality of wall studs. The wall studs are placed at a distance from each other so as to define insulating spaces in between them. The sheathing material is attached to the wall studs. The manufactured stones are attached to the sheathing material. A method of assembling a wall structure is also disclosed. The method of assembling a wall structure comprising the step of fastening an insulated stone having a R-value of at least R8 to a wall sub-structure having an R-value less than R20.

FIELD OF THE INVENTION

The present invention generally relates to the field of manufactured stones and bricks. More specifically, the invention relates to an insulated manufactured stone.

BACKGROUND OF THE INVENTION

Building houses using stones goes back to the dawn of times. Through history, stone has been used to build from small houses to gigantic cathedrals. Because of the longevity of the buildings made from this material, its use has always been associated with quality and luxury.

However, the drawback of building a house from stone, not withstanding the cost of the material itself, is the involved labor and skill required to dress and mortar the stones. More conveniently, bricks have been developed. Because of their regular shape, it took much less time and skill to install them than to install stone. More recently, the same principle has been applied to stones: manufactured stones, made of crushed stones mixed with Portland cement have been manufactured. Although not all exactly the same dimension as the others, these stones nevertheless often have dimensions that render them easy to combine with each other. Hence, these days, the look of stone can be had with a product that is practically as easy to install as bricks. Because they are closely related, and for the sake of simplicity, the term “stone” will from now on in the present description be understood to encompass the term “brick” as well. However, manufactured stones are still more expensive than the cost of alternative building siding, such as vinyl siding, and efforts are still deployed to lower their cost.

Solutions have been proposed where the cost of manufactured stones have been decreased, for example, by the use of a core filling material. U.S. Pat. No. 3,512,327 to La Padura discloses using a light weight core in a brick to produce a product that has the appearance of a polished stone, but at a fraction of its weight, and most probably cost. U.S. patent application Ser. No. 10/875,044 to Lane et al. discloses a wall panel mimicking the appearance of stones on an external face and using a foam core inside. Again, the cost per surface unit is probably somewhat decreased, although ease of installation and durability of this type of siding, because of its thin external coating is questionable.

However, these solutions focus solely on the stones themselves. None consider an integrated approach to the typical North-American house construction, which, if properly done, could yield even further cost savings. With the cost of housing on the rise since the few last years, there is definitely a need for further cost savings of building siding such as manufactured stones.

SUMMARY OF THE INVENTION

It is an object of an aspect of the present invention to provide a stone that overcomes or mitigates one or more disadvantages of known stones, or at least provides a useful alternative.

It is an object of another aspect of the present invention to provide a wall construction that overcomes or mitigates one or more disadvantages of known wall constructions, or at least provides a useful alternative.

The invention provides the advantages of providing a stone enabling a wall construction that is cheaper than known wall constructions while substantially retaining the insulating properties of known wall constructions. Alternatively, the invention may provide the advantage of improving the insulation properties of known wall construction while retaining substantially the save cost.

In accordance with an embodiment of the present invention, there is provided a manufactured stone comprising a body and an insulating core. The body has a base, an exterior portion and an interlocking mechanism. The exterior portion has an aesthetic face. The interlocking mechanism is adapted to interlock with another similar manufactured stone. The insulating core is at least partly imbedded in the body. The insulating core has a thickness sufficient to provide the body with an R-value of at least R8.

In accordance with another embodiment of the present invention, there is provided a wall structure comprising, from an interior to an exterior, a wall framing, a sheathing material and a plurality of manufactured stones. The wall framing is made of a plurality of wall studs. The wall studs are placed at a distance from each other so as to define insulating spaces in between them. The sheathing material is attached to the wall studs. The manufactured stones are attached to the sheathing material.

In accordance with another embodiment of the present invention, there is provided the use of the manufactured stone in the construction of the wall structure.

In accordance with another embodiment of the present invention, there is provided a method of assembling a wall structure comprising the step of fastening an insulated stone having a R-value of at least R8 to a wall sub-structure having an R-value less than R20.

In accordance with yet another embodiment of the present invention, there is provided a manufactured stone that comprises a body and an insulating core at least partially imbedded in the body. The body has a base, an exterior portion, a mid portion and an interlocking mechanism. The exterior portion has an aesthetic face. The mid portion is placed between the base and the exterior portion and is recessed both from the base and the exterior portion. The interlocking mechanism is adapted to interlock with another similar manufactured stone.

BRIEF DESCRIPTION OF DRAWINGS

These and other features of the present invention will become more apparent from the following description in which reference is made to the appended drawings wherein:

FIG. 1 is a perspective view of a manufactured stone in accordance with an embodiment of the present invention.

FIG. 2 is a front view of a manufactured stone in accordance with another embodiment of the present invention.

FIG. 3 is a cross-sectional view of the manufactured stone of FIG. 2.

FIG. 4 is perspective view of an assembly of two manufactured stones similar to the one of FIG. 1.

FIG. 5 is a front view of a manufactured stone in accordance with another embodiment of the present invention.

FIG. 6 is a perspective view of a wall structure using the manufactured stone of FIG. 1 in accordance with another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to manufactured stones or bricks (hereinafter referred to under the single term “manufactured stone”, but understood to include both manufactured stones and bricks) having a core permitting the manufactured stone to reach an insulation value (known as an R-value) of at least R8.

A material's R-value is a measure of its resistance to heat flow. The higher the R-value, the more the material insulates. The Si units for thermal resistance are K·m²/W. R-values can be calculated from thermal conductivity, k, and the thickness of the material, t by using the equation R=t/k.

Typically, at least in the northern part of North America wall structures of houses commonly use wall studs made of lumber having a cross section of 1.5 inch by 5.5 inches (referred to as a 2×6) and defining spaces in between them where insulating material, such as mineral wool or foam, is placed. Such wall structure has an R-value of R20. Typical exterior finishing such as bricks or stones do not commonly insulate much and therefore do not significantly add to the R-value. However, by replacing such typical exterior finishing by a manufactured stone having an R-value of at least R8, it is possible to build a wall structure having only an R-value of R12. This corresponds to a wall structure made from lumber having a cross section of 1.5 inch by 3.5 inches (referred to as a 2×4). Since 2×4s are cheaper than 2×6s, the total cost of the wall construction decreases for a similar aspect exterior wall siding. Moreover, because the wall is thinner, the foundation may also be thinner and smaller for the same interior living surface. It goes without saying that substantial savings follow from this new wall construction. Alternatively, the manufactured stone of the present invention may be installed to wall construction made of 2×6s. The insulation properties are then increased, which in turn reduce the energy cost related to heating or cooling of the house.

Reference is now made to FIG. 1. FIG. 1 depicts a manufactured stone 10. The manufactured stone is made of a body 12. The body is divided into a base 14, an exterior portion 16, a mid portion 18, an interlocking mechanism 20 and an insulating core 22.

The body 12 is typically made of a concrete mixture comprising Portland cement. Optionally, the concrete mixture may also include fiber reinforcement, which help render the manufactured stone 10 less brittle.

The base 14 is typically flat and is designed to contact a surface on which the manufacturing stone 10 is mounted. The exterior portion 16 has an aesthetic face 24 which is typically made to imitate different types of natural or artificial surfaces such as stone or brick. Other surfaces could possibly be imitated as well, although most people like the look of natural stone. By adding different pigments to the concrete mixture, different colors are generated.

The mid portion 18 is located between the base 14 and the exterior portion 16, both from which it is recessed. The interlocking mechanism 20, which is adapted to interlock with another similar manufactured stone 10, is located in the mid portion 18. The interlocking mechanism 20 may take different forms and shapes. However, it has been found that a simple tongue 26 works very well for interlocking with other manufactured stones. The tongue 26 extends from the mid portion 18 on two sides only. The tongue 26 projects both from the base 14 and from the exterior portion 16. The tongue 26 is adjacent to the base 14 and is only approximately half the height of the mid portion 18. This leaves room to put mortar on top of the tongue 26 when assembled with other similar manufactured stones. FIG. 2 is now concurrently referred to. Two holes 28 are located in the tongue 26. Both holes 28 are placed so that they hold different sides of the manufactured stone 10. The holes 28 are used to receive a fastener so that the manufactured stone 10 may be fastened to a mounting surface, as will be discussed in more details later. A configuration with only one hole could be used, although the two hole configuration may be chosen since the manufactured stone 10 may not accidentally be rotated once fastened.

The insulating core 22 is at least partially imbedded in the body 12. Optionally, the insulating core 22 may have a thickness sufficient to provide the body with an R-value of at least R8. Depending on the type of material used for the insulating core 22, this thickness will vary. Since the R-value of different types of foams is well documented by foam manufacturer, a person skilled could easily figure the thickness required to get to an R8 value. If other materials than foam are used, then the R-value may be derived either from literature or from testing. An insulating core 22 made of polystyrene and having a thickness of 1.5 inch has shown good results. Conveniently, polystyrene is much lighter than the concrete mixture of the base 12. Hence, the manufactured stone 10 is advantageously much lighter than a standard manufactured stone without foam core. Because the manufactured stone 10 is lighter, it is cheaper to ship, easier to install and lighter on a wall structure on which it will eventually be installed. Typically, the manufactured stone 10 of the present invention is 60% lighter than a similar manufactured stone without foam core.

The insulating core 22 may partially or totally be imbedded in the body 12. If it is partially imbedded, the base 14 does not cover the insulating core 22, such that the insulating core 22 is flush with an exterior side of the base 14. This is depicted in FIG. 3, which is concurrently referred to. By properly designing the insulating core 22 so that it is as large as possible, it is possible to get an R8 value on at least 90% of a surface of the manufactured stone 10.

FIG. 4 is now referred to. Because it is recessed, the mid portion 18 creates an undercut 32. This undercut 32 is used to retain mortar 34 when manufactured stones 10 are placed against each other and fastened in place. This undercut is also shown in FIG. 3.

FIG. 5, now referred to, depicts another embodiment of the invention where the exterior portion 16 may be divided by false joints 30 in the aesthetic face 24. By doing so, and combined with the fact that the manufactured stone 10 of the present invention is much lighter than conventional manufactured stones, it is possible to manufacture larger stones which look like many individual stones. This further saves installation costs.

FIG. 6, which is now referred to, depicts a wall structure 36 in accordance with the present invention. The wall structure 36 comprises a wall framing 38 made of wall studs 40. The wall studs 40 are placed at a distance from each other so as to define insulating spaces 42 in between them. Typically, for exterior walls, the wall studs 40 are placed at every 16 inches. Although wall studs are often made of lumber, it would be possible to make them of another suitable material, such as steel, for example. A sheathing material 44, such as a plywood, oriented strand board or other adequate structural panel made of wood or not, is attached to the wall studs 40 and closes the wall structure 36 from the outside. The manufactured stones 10 are fastened to the sheathing material 44, preferably by the use of screws in the holes 28 (not shown). A vapor barrier membrane 46 may be used in between the manufactured stones 10 and the sheathing material 44.

As already discussed, the wall structure 36 of the present invention may do without large wall studs made of 2×6 lumber and use 2×4 lumber instead, which are cheaper.

The wall structure 36 is completed, on the inside, by filling the insulating spaces 42 with insulating material 48 and a gypsum panel 50 for closing the inside of the wall structure 36. The gypsum panel 50 is attached to the wall framing 38 and more precisely to the wall studs 40.

The wall framing 38, with the insulating material 48, sheathing material 44 and gypsum panel 50 in place gets an R-value of R12, when wall studs 40 made of 2×4 lumbers are used. When the manufactured stones 10 are installed, which themselves have an R-value of R8, both R-values add up and the total R-value rises to R20.

If it is desired to further increase the R-value, it is possible to install an insulating foam (not shown) in between the vapor barrier membrane 46 and the manufactured stones 10. Moreover, it would also be possible to revert to a wall structure 36 that uses wall studs of 2×6, which would bring the R-value to R28.

To further secure the manufactured stones 10, it is possible to use a plastic cement on the sheathing material 44, or on the vapor barrier membrane 46 if present, and lay the manufactured stones 10 in the cement. Fastening the manufactured stones 10 with adequate fasteners, such as screws, is still recommended.

Advantageously, the wall structure 36 of the present invention yields the possible following savings, when lumbers of 2×4 are used as wall studs instead of lumbers of 2×6: a 20% reduction in the volume of concrete needed for the foundation (since the wall structure is thinner), 33% reduction in the volume of wood needed and a reduction of 3 inches in the total thickness of the wall structure 36 (2 inches from switching from 2×6s to 2×4s plus the elimination of a 1 inch air space between the sheathing material and a conventional stone).

The present invention has been described with regard to preferred embodiments. The description as much as the drawings were intended to help the understanding of the invention, rather than to limit its scope. It will be apparent to one skilled in the art that various modifications may be made to the invention without departing from the scope of the invention as described herein, and such modifications are intended to be covered by the present description. 

1. A manufactured stone comprising: a body having; a base; an exterior portion, said exterior portion having an aesthetic face; and an interlocking mechanism adapted to interlock with another similar manufactured stone; an insulating core at least partly imbedded in said body, said insulating core having a thickness sufficient to provide said body with an R-value of at least R8.
 2. The manufactured stone of claim 1 further comprising a mid portion placed between said base and said exterior portion, said mid portion being recessed both from said base and said exterior portion.
 3. The manufactured stone of claim 2 wherein said interlocking mechanism is a tongue, said tongue partially extending from said mid portion and projecting both from said base and said exterior portion, said tongue being adjacent to said base, said tongue being thinner than said mid portion, said tongue having at least one hole adapted to receive a fastener for fastening said stone in place, said tongue being adapted to mate with a mid portion of a similar manufactured stone.
 4. The manufactured stone of claim 3 wherein said tongue is extending from said mid portion in at least two different directions.
 5. The manufactured stone of claim 4 wherein said insulating core is made of polystyrene.
 6. The manufactured stone of claim 5 wherein said insulating core is totally imbedded in said body.
 7. The manufacturing stone of claim 6 wherein said body is made of a concrete mixture comprising fiber reinforcement.
 8. The manufactured stone of claim 1 wherein said stone has said at least R8 value on at least 90% of its surface.
 9. The manufactured stone of claim 1 wherein said exterior portion comprises a false joint on said aesthetic face.
 10. A wall structure comprising, from an interior to an exterior: a wall framing made of a plurality of wall studs, said plurality of wall studs being placed at a distance from each other so as to define insulating spaces in between them; insulating material in said insulating spaces; a sheathing material attached to said wall studs; and a plurality of manufactured stones as defined in claim 1, said plurality of manufactured stones being attached to said sheathing material.
 11. The wall structure of claim 10 wherein each of said plurality of wall studs measures approximately 1.5 inch by at least approximately 3.5 inches.
 12. The wall structure of claim 11 further comprising a vapor barrier membrane between said plurality of manufactured stones and said sheathing material.
 13. The wall structure of claim 12 further comprising a gypsum panel attached to said wall framing opposite from said sheathing material.
 14. The wall structure of claim 13, further comprising an insulating foam in between said vapor barrier membrane and said plurality of manufactured stones.
 15. The use of said manufactured stone of claim 1 in the construction of a wall structure, said wall structure comprising, from an interior to an exterior: a wall framing made of wall studs, said wall studs being placed at a distance from each other so as to define insulating spaces in between said wall studs; a sheathing material attached to said wall studs; wherein said manufactured stone is attached to said sheathing material.
 16. A method of assembling a wall structure comprising the step of: fastening an insulated stone having a R-value of at least R8 to a wall sub-structure having an R-value less than R20.
 17. The method of claim 16 further comprising the step of assembling wall studs of approximate dimensions of 1.5 inch by 3.5 inches to provide said wall sub-structure.
 18. A manufactured stone comprising: a body having; a base; an exterior portion, said exterior portion having an aesthetic face; a mid portion placed between said base and said exterior portion, said mid portion being recessed both from said base and said exterior portion; and an interlocking mechanism adapted to interlock with another similar manufactured stone; an insulating core at least partially imbedded in said body.
 19. The manufactured stone of claim 18 wherein said interlocking mechanism is a tongue, said tongue partially extending from said mid portion and projecting both from said base and said exterior portion, said tongue being adjacent to said base, said tongue being thinner than said mid portion, said tongue having at least one hole adapted to receive a fastener for fastening said stone in place, said tongue being adapted to mate with a mid portion of a similar manufactured stone.
 20. The manufactured stone of claim 19 wherein said insulating core has a thickness sufficient to provide said body with an R-value of at least R8. 